The plane crashed on the property of the Flomo company at 698 Route 46 West shortly after 3am on Friday.
Both men were taken to St. Barnabas Medical Center. The pilot, identified as George Maddox, 54, of Sinking Springs, Pa., was listed in critical condition. Co-pilot Sanil Gopinath, 42, of Laurel, Md., was listed in serious condition.
Route 46 is open between Industrial Avenue and Green Street, but only one lane is getting through westbound. Green Street is closed at the perimeter of the airport.
When emergency personnel arrived, they found the pilot and co-pilot alert and sitting at a bus stop.
The airport was closed following the crash, but reopened at about 7am.
The cause of the crash are yet known.
Bergen County police and fire crews were on the scene.
The Port Authority says that the National Transportation Safety Board (NTSB) is investigating the crash.
The plane was flying out of Reading, PA and was carring blood specimens for Quest Diagnostics.
Teterboro Airport is a general aviation facility operated by the Port Authority of New York & New Jersey.
In 2005, a corporate jet went off the runway at Teterboro, crashed through a fence and crossed a highway before smashing into a warehouse. Twenty people were injured.